1. Technical Field
The invention relates to the field of telephony and, more particularly, to exchanging information between service logic components in a telephony network.
2. Description of the Related Art
Telecommunication companies continually create new telephony services and/or features (hereafter “services”) to be offered to subscribers. Often, these services require the interaction of multiple service logic components. One common example is call control service logic and transaction service logic. While the call control service logic is associated with setting up the voice communication aspects of a telephone call, the transaction service logic provides the foundation for non-voice processing aspects of a telephone service such as 800 number translation, database querying, Short Message Service (SMS), Local Number Portability, Wireless Application Protocol (WAP), and other transaction-based services or service components. Thus, to implement a given telephony service, call control service logic often must interact with transaction service logic.
For example, if a telephone call is to be transferred to another directory number as a result of a number translation performed by the transaction service logic, the call control service logic must be able to obtain the call transfer information from the transaction service logic. That is, responsive to receiving a telephone call, the call control service logic must query the originating service, in this case the transaction service logic, to determine how to handle the telephone call. Traditionally, this interaction between different service logic components has been accomplished through the use of a service-to-service messaging protocol.
Through the service-to-service messaging protocol, a receiving service can determine contextual information regarding a given telephone call. Accordingly, the receiving service, in this case the call control service logic, with reference to the contextual information, can process the telephone call. The service-to-service messaging mechanism, however, has disadvantages. One such disadvantage is that the originating service must remain active to provide information in the form of multiple messages to any receiving services in need of contextual information to complete a call. The originating service becomes the “master” and the receiving service becomes the “slave”. The originating service remains active solely to provide needed messaging functions for receiving services despite the fact that the primary function of the originating service has completed. In consequence, costly memory and processor resources are consumed for the duration of the service-to-service lifetime.
Another disadvantage is that the cost of updating a service-to-service messaging protocol can be very high. Notably, each service logic component that relies on the service-to-service messaging protocol must be updated along with the protocol itself. Thus, at a minimum, two service logic components must be updated for a given protocol enhancement. In consequence, multiple nodes within a telephony network may have to undergo a coordinated update process.
These types of issues have been a hindrance to the development of the Intelligent Network (IN) as well as Advanced Intelligent Network (AIN). Although multiple protocols such as SR-3511, 1129 CORE, CORE INAP, and the like have been developed, no global standard has emerged. Additionally, the cost model for maintaining a service control point (SCP) has begun to rival that of maintaining a telephony switch. Moreover, as services implemented using the SCP cost model are resource intensive, the need to utilize memory and processor resources for the duration of the service-to-service lifetime further increases the cost of service implementation, deployment, and maintenance.